Lakshmi, first off, OBC and EWS are 2 different Categories, You cannot be eligible for both the Categories. EWS is a reservation for Candidates belonging to General Category and whose annual income is less than 8 lakhs per annum from all sources. So if you belong to OBC Category, you cannot claim EWS Category. And both the Categories have their own cut offs depending on the no.of seats available and no.of Candidates qualified. Now regarding Vellore Medical College, if you meant CMC Vellore, CMC Vellore doesn't participate iin All India Counselling. You have to participate in Tamilnadu's State Counselling for Management Quota seats. And you have to register in prior to CMC to apply for MBBS there. But to answer your question you will need atleast 550 and more for a seat in CMC, Vellore if you do not belong to Tamilnadu. In 2018, under SVU area, 458 marks secured a seat in SVU Medical College under BC Category. Now this is 2018 data and cut offs change every year. Cut offs change every year depending on various factors such as no.of Candidates appearing for the exam, no.of Candidates qualified, top NEET score and difficulty of the exam. So for 2020, you will need atleast 550-575.